Failed to load model with assimp, access violation - c++

Question

I got a problem when I want to import a simple model using assimp, whenever I compile the code it throws:
0xC0000005: Access violation reading location 0x00000000.
I know this is something about a null pointer but I just can't find it, the code goes as follows:
Model::Model(GLchar* path)
{
loadModel(path);
}
void Model::loadModel(std::string path)
{
Assimp::Importer import;
const aiScene* scene = import.ReadFile(
path,
aiProcess_Triangulate |
aiProcess_FlipUVs);
if (!scene || scene->mFlags == AI_SCENE_FLAGS_INCOMPLETE || !scene->mRootNode){
std::cout << "ERROR::ASSIMP::" << import.GetErrorString() << std::endl;
return;
}
directory = path.substr(0, path.find_last_of('/'));
aiNode* node = scene->mRootNode;
for (GLuint i = 0; i < node->mNumChildren; i++){
aiMesh* mesh = scene->mMeshes[node->mMeshes[i]];
meshes.push_back(processMesh(mesh, scene));
}
for (GLuint i = 0; i < node->mNumChildren; i++){
processNode(node->mChildren[i], scene);
}
}
I use this Model class as a global variable:
//include stuff
//other global variable
Model mymodel("D:/Project/xxx/xxx.obj");
int main(){
//...
return 0;
}
The thing is that the error happens just between the line directory = path.substr(0, path.find_last_of('/')); and the line aiNode* node = scene->mRootNode; so I don't know how to debug it, could anyone tell me how to fix this? I use Visual Studio 2013-64 and assimp-3.1.1.
Thank you very much.

Answer 1

I think the problem could be in this part of the code:
Model::Model(GLchar* path)
{
loadModel(path); // path is declared a string in loadModel function - type conversion might not be happening as expected.
}
Check, if you are getting a correct/valid value in the path variable on the line:
directory = path.substr(0, path.find_last_of('/'));
This link might be helpful:
GLchar could not be resolved
Note: I am not familiar with OpenGL, but looking at the error you are getting this is the first place I would check.